1. Field of the Invention
The present invention relates to fastening devices and, more particularly, to a novel fastening device of a staple type having means for substantially locking the legs of the staple to a supporting base so that the staple cannot be removed from its installation.
2. Brief Description of the Prior Art
In the past, it has been the conventional practice to employ staples having a pair of prongs joined by a center section which, when driven by an impact member, causes the prongs to enter a supporting material such as wood or the like. Generally, a wire length such as fence wire is positioned between the prongs and is substantially captured by the cross member of the staple when the staple is fully driven into the support member.
Although such conventional staples have been effective for holding a wire to the supporting member, difficulties and problems have been encountered which stem largely from the fact that, after time, the staple tends to withdraw from its installation in the wood base. Also, any undue stress or pressure against the wire will cause the staple to withdraw from its installation. Additionally, electrical problems are sometimes encountered when metal staples are used in combination with metal fence wire. Such problems include antenna interference so that television or radio reception is adversely affected at nearby locations.
Also, it is to be particularly noted that when driving a conventional staple into a wood base, the prongs are pointed to permit easy penetration; however, the prongs are parallel to one another in fixed spaced relationship so that extraction from installation can be readily achieved. Such extraction is not necessarily of benefit and greatly reduces the effectiveness of conventional staples.
Therefore, a long-standing need has existed to provide a novel staple wherein the prongs cannot be readily withdrawn from the installation and which will be suitably insulated from wire or other members that are being held by the staple so that electrical interference or adversities are not encountered.